Eikonal equation
= Eikonal equation
{wiki}
The leading WKB phase obeys an eikonal equation. For a local dispersion relation $\omega=\Omega(k;x,t)$ and $k=\nabla\theta$, it is
$$
-\partial_t\theta=\Omega(\nabla\theta;x,t).
$$
= Eikonal equation
{wiki}
The leading WKB phase obeys an eikonal equation. For a local dispersion relation $\omega=\Omega(k;x,t)$ and $k=\nabla\theta$, it is
$$
-\partial_t\theta=\Omega(\nabla\theta;x,t).
$$